Cytotoxic and Apoptotic Effects of Tin(IV) Complexes Containing a Schiff Base Derived from Cephalexin on a Breast Cancer Cell Line

Metal complexes containing heterocycles have wide pharmaceutical and medicinal applications. The biological activities of the complexes are influenced by a range of factors, including the identity of the ligands coordinated to the tin ion and the heteroatoms contained in them. Additionally, stabilizing the bonds between the tin atom and the ligand impacts the effectiveness of organotin complexes as biologically active molecules. This study involves the synthesis of new metal complexes and their evaluation for cytotoxic and apoptotic effects against human breast cancer cells (MCF-7). The reaction of cephalexin and 4-(dimethylamino)benzaldehyde in boiling methanol gave the corresponding Schiff base in a good yield. Subsequently, the reactions of disubstituted (methyl, butyl, and phenyl) tin chlorides and the Schiff base in boiling methanol produced the corresponding organotin(IV) complexes in high yields. The effect of the synthesized organotin complexes on MCF-7 was assessed. Based on the half-maximal inhibitory concentration (IC50) results, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay proved that all the organotin complexes effectively suppressed cancer growth. The dibutyl derivative of the three complexes tested had higher anticancer activity against MCF-7 cells than the dimethyl and diphenyl compounds. The IC50 values for the synthesized tin complexes ranged between 95 and 71 μg/mL. Based on the concentration of the complex, a high content screening technique (HCS) assay showed a decrease in MCF-7 cell line cell viability. This decrease was proportional to the viable cell count, membrane permeability, total nuclear intensity, mitochondrial membrane potential, and cytochrome C levels.